Design Conditions; Lats Calculated Refrigerant Charge - LG Multi IV Engineering Manual

REFRIGERANT PIPING DESIGN
Consider refrigerant safety in all designs.
LG Multi V IV outdoor units ship from the factory with a charge of R410A refrigerant. This charge serves as the base charge and will not be
sufficient for the system to operate. A trim charge will need to be added after the system is installed that is based on system design. LATS
Multi V piping design software will calculate the size of the refrigerant piping and calculate the refrigerant charge; this added trim refrigerant
charge is shown on the LATS Multi V output.
The example LATS Multi V design software report below shows both the base charge and the calculated trim charge (Tables 43-48). The
information used in the tables below are obtained from a LATS-generated report.
Project Name: Multi V IV Heat Recovery System Test Update System No: 1/1
Table 43: Design Conditions.
Indoor
DB (°F) WB (°F)
80.6 67.1
Table 44:
Max. Indoor
Model Name Unit
Connectivity
ARUB121DTE4 20
Product Charge = Factory charge of outdoor unit.
1
Additional Ref Amount = Trim charge.
2
Table 45:
Index (from Piping Dia. (Inches)
LATS selection) Liquid : Vapor
P28 1/2 : 3/4 : 1+1/8
P22 3/8 : 3/4 : 7/8
P0 1/4 : 1/2
P1 3/8 : 5/8
P27 3/8 : 5/8 : 3/4
P21 3/8 : 1/2 : 5/8
It is imperative to know the "as-built" physical length of each segment of liquid line, to calculate the
1
total refrigerant charge required. An accurate "as built" field-verified piping diagram is required to verify
within LATS that piping is within limits, proper pipe sizing, and refrigerant charge.
Table 48: Indoor Units.
Model Name
ARNU183SCL4
ARNU183TQC4
ARNU243BGA4
ARNU123SBL4
ARNU123SER2
ARNU183NJA4
ARNU123VEA2
ARNU183CFU4
Total
134 |
Summer
Outdoor
RH (%) DB (°F) WB (°F)
50 93.9
Max. Total Indoor Unit to
Over Load Outdoor Unit
(kBtu/h/%) Ratio
156.0 (130%) 1.26:1
Length (Feet)
20.0
15.0
130.0
50.0
35.0
16.0
Quantity
1
1
1
2
1
1
1
1
9
©
Indoor
DB (°F) WB (°F)
73.9 68.0 56.8
Rated / Corrected Capacity
Product Additional
Charge Ref. Amount
1 2
(lbs.) (lbs.)
Cooling
23.6 18.26 120.0 / 126.0 135.0 / 127.8
Table 46: Branches / Headers / Common Pipes / Heat Recovery Units.
Model Name
1
ARBLB03321
PRHR042A
PRHR032A
PRHR022A
Table 47: Accessories.
Model
Index Quantity
Name
IDU PT-UMC
Wall Mounted (18 MBh)
Ceiling Cassette - Four-Way (18 MBh)
Ceiling-Concealed Ducted - High Static (24 MBh)
Wall Mounted (12 MBh)
Art Cool Mirror (12 MBh)
Vertical / Horizontal Air Handling Unit (18 MBh)
Convertible Surface (12 MBh)
Floor Standing - Without Case (18 MBh)
Winter
RH (%) DB (°F)
50 17.1
Rated / Corrected
(kBtu/h) Power Input (kW)
Heating Cooling
8.5 / 9.2
Quantity
Description
1 Std. Grille - Four-way Cassette (TN, TM, TP)
Description
-
Outdoor
WB (°F)
16.2
Heating
8.7 / 10.6
1
1
1
1